#rsisb Roll no.239 Foundation Level **Trigonometry** is the fascinating branch of mathematics that explores the relationships between **angles and the sides of triangles**. The word itself comes from Greek roots meaning “triangle” and “measurement.” At the heart of trigonometry are three important ratios: **sine, cosine, and tangent**. These help us understand angles and calculate unknown lengths and measurements. genui{"trigonometry_vectors":{"type_id":"UNIT_CIRCLE"}} Trigonometry is used far beyond the classroom. It plays an important role in **engineering, architecture, astronomy, physics, navigation, computer graphics, and construction**. The story of angles shows us how a simple mathematical idea can become a powerful tool for understanding the world around us.